The researchers also tracked activity in the nucleus accumbens, a part of the brain involved in the processing of rewards. They observed elevated activity in the nucleus accumbens when a subject's rank within the group increased. "That shows that the task was motivationally important to people," Quartz says. "When they saw their rank go up, that was a reward."
Similar to the previous work on offering money for higher scores. Not very relevant to high-stakes testing, where people already have strong reason to want to succeed - and so have motivation.
Assuming this effect is significant, how could we exploit it by optimising group structures so as many people as possible think they are high status?
Anyone heard of this effect being replicated? It seems awfully steep (17 point drop?) to be believed. I ask because ideally we want to maximize cognition to maximize workplace and personal success, and this seems very detrimental to many people who are in lower-status positions within the hierarchy. It also may explain why some people seem to perform worse when their boss is hovering over them. If this is true, then there is some truth when people say, "Don't worry about what others are thinking".
An alternate explanation: It is possible that those with lower baseline IQ experience more fatigue after taking a mentally stimulating test, so that they experience a greater drop in cognition when taking another one back-to-back. Did the researchers reveal the times between the paper-and-pencil test and the computer-based one? The article doesn't say.
EDIT: The paper is free and is found below. Apparently the computer-based test was taken soon after based on the wording of the authors. I wish the test was given the day after to control for mental fatigue. Too bad, seems like they were on to something there.
http://rstb.royalsocietypublishing.org/content/367/1589/704.full
http://media.caltech.edu/press_releases/13492
To investigate the impact of social context on IQ, the researchers divided a pool of 70 subjects into groups of five and gave each individual a computer-based IQ test. After each question, an on-screen ranking showed the subjects how well they were performing relative to others in their group and how well one other person in the group was faring. All of the subjects had previously taken a paper-and-pencil IQ test, and were matched with the rest of the group so that they would each be expected to perform similarly on an IQ test.
At the outset, all of the subjects did worse than expected on this "ranked group IQ task." But some of the subjects, dubbed High Performers, were able to improve over the course of the test while others, called Low Performers, continued to perform below their expected level. By the end of the computer-based test, the scores of the Low Performers dropped an average of 17.4 points compared to their performance on the paper-and-pencil test.
"What we found was that sensitivity to the social feedback of the rankings profoundly altered some people's ability to express their cognitive capacity," Quartz says. "So we get this really quite dramatic downward spiraling of one group purely because of their sensitivity to this social feedback." Since so much of our learning—from the classroom to the work team—is socially situated, this study suggests that individual differences in social sensitivity may play an important role in shaping human intelligence over time.